Automatic telephone system



Patentd Mar. 14, 1922-. 2 SHEETS SHEET I.

T.v LENAG'HAN.

' AUTOMATIC TELEPHONE SYSTEM.

APPLICATION- FILED NOV. 2. 1920.

A rrm/v r T. LENRG'HAN.

AUTOMATIC TELEPHONE SYSTEM.

AFPLTCATION FILED NOV. 2, 1920..

1,409,737, Patehted Mar. 14,1922; v 2 SHEETSSHEET 2- PATENT OFFICE.

THOMAS LENAGI-IAN, OF CROYDON, ENGLAND.

AUTOMATIC TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented Mar. 14, 1922.

I AppIication filed; November 2, 1920. Serial No. 421,382.

To (a?! 20/ 10772, 4/: may concern.

Be it known that I, THOMAS LENAGHAN. a subject of the King Great Britainand Ireland, residing at Croydon, in the county of Surrev. England, havenvented Improvements in Automatic Felephone Systems. (a continuation ofmy prior pplication filed April 28. 1920, Ser. l lo. 371288 as-to allmatter common to both ipplications, "for which I have filed anapplication in England, April 23, 1919, No. 10202,) of which thefollowing is a specification.

This invention relates to terminal or con tact banks as used inautomatic telephone *i ching systems, but more particularly in thesystem described in my co-pending application No. 377,288, but it is tobe understood that the scope of its use is not coniined to the saidsystem. The principal object o l this invention is the provision or anumber oi contacts so shaped that switch members having access to thesaid contacts will as they sweepover the contacts encounter surfacesthat are at all times in condition to ensure perfect contact.

This is secured by making the several contacts oi angular formation,that is to say with portions inclined outwardly and upwardly in relationto the bank as a whole.

A further object is, by the provision of stamped up projections or lugsin the contacts to provide an economical method of holding the contactsin their banks.

A further improvement due to the shape of the stamped contacts, andtheir assembly, is that the vertical distance the switch has to travelwhilst disengaged from a contact is reduced to a minimum whilst stillensuring the necessary insulation between the con: tacts--a furtherimprovement is thus also attained in that the distance of contact,whilst the switch is travelling in an upward direction, is increased togive almost the total separating distance between the contacts.

Referring to the drawings:

Fig. 1 is a front elevation of a bank as 'sembly; Fig. 2 an endelevation of same,

and Fig. 3 a section through the line 33 Fig. 1. Fig. 4: is a plan ofthe connecting bars to which the contacts are riveted or interconnectedby other means; Fig. 5 is a section on the line 55 Fig. 4. Fig. 6 asection on the line 5-6 Fig. 4:. Fig. 7 a view semi-diagrammatic showingthe switch fintions, part for incoming connections and part for theconnection of control recorders, as described in my application filedApril 28. 1920, Ser. No. 377,288, the said contacts being available forconnections by the switch members on both faces of the bank as shown inFig. 2. In Fig. 3 is shown the interconnection of the contacts (1 whichare preferably punchings, Figs. a, 5 and 6 showing more clearly thedetails of the arrangement. The contacts Fig. 9 are held in the bank byhorizontal separating strips (Z, leaving the centre of the bank hollow,these strips may be slotted on either their vertical or horizontal facesas desired to engage the contact, each projection e on which engages inthe vertical slot if used, or on the face of the strip if the horizontalslot is used, thus preventing any movement of the contact. As analternative to the foregoing the contact and bars may be held by amoulded insulation. Fig. 7 shows a view of the switch members S- makingcontact with the bank contacts C. Thesaid switch members do not formpart of this specification and are fully described in my copendingapplication No. 377,288 be ing only illustrated herein to show thefunctions of the bank contacts. The switches S travel in the directionshown by the arrows, the fingers F pivoted at the point P sweeping overthe various contacts; as herein illustrated, the distance D in which thefinger F is out of contact with a bank member is reduced to the minimumwhilst the dis tance of contact D is at a maximum, being the totalseparating distance D less Di.

By reason of the shape of the contacts 0 it will be selfevident that thesurfaces engaged by the fingers F so overhang that dust cannotaccumulate thereon.

That I claim is 1. In a telephone contact bank, a plurality of contactmembers each of which is formed on both faces, each contact member beingformed with an angular portion presenting an overhanging surface whichis inclined outwardly and upwardly in relation to the bank as a whole. 7

8. In a telephone contact bank, a plurality of contact members each ofwhich is formed with an angular portion presenting an overhangingsurface which is inclined upwardly and outwardly in relation to the bankas a whole andwith punched up projections, and separating insulators forsuch contact members engaged by such projections whereby the contactmembers are ren dered self holding in the bank, substantially asdescribed.

4. In a telephone system, a plurality of contact members each formedwith a pair of angular portions presenting overhanging surfaces whichare inclined upwardly from the horizontal and with punched upprojections and insulating members engaged by said projectionsseparating them in several horizontal levels so as to render them selfholding in a bank capable of being swept over upwardly by movableswitches on both faces, substantially as described.

5. In a telephone system, a plurality of contact members arranged inseveral horizontal levels constituting a vertical bank capable of beingswept over by'switches, each contact member being formed with an angularportion presenting an overhanging surface which is inclined outwardlyand upwardly in relation to the bank as a whole and a plurality ofconductors interconnecting the. contact members on one horizontal level,the said contact members being rouped to accommodate one or morecircuits on that level.

6. In a telephone system, a plurality of being subdivided in order thatthe several contact members may be available for the connection of theseveral component parts of a given circuit.

Signed at London, England, this 14th day of October, 1920.

THOMAS LENAGHAN.

